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1.
This paper considers the job (lot) scheduling problem for two-stage flow shops in which the movement of transfer batches (sublots) from the first stage to the next are allowed. Set-up, processing and removal times are considered as separable and independent of the order in which jobs are processed at any of two stages. An optimal transfer batch sizing and scheduling algorithm which has an objective of minimizing the maximum flow time (makespan) is developed and demonstrated by a numerical example.  相似文献   
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This study aims to clarify the effects of carbon activation type and physical form on the extent of adsorption capacity and desorption capacity of a bi-solute mixture of phenol and 2-chlorophenol (2-CP). For this purpose, two different PACs; thermally activated Norit SA4 and chemically activated Norit CA1, and their granular countertypes with similar physical characteristics, thermally activated Norit PKDA and chemically activated Norit CAgran, were used. The thermally activated carbons were better adsorbers for phenol and 2-CP compared with chemically activated carbons, but adsorption was more reversible in the latter case. 2-CP was adsorbed preferentially by each type of activated carbon, but adsorption of phenol was strongly suppressed in the presence of 2-CP. The simplified ideal adsorbed solution (SIAS) model underestimated the 2-CP loadings and overestimated the phenol loadings. However, the improved and modified forms of the SIAS model could better predict the competitive adsorption. The type of carbon activation was decisive in the application of these models. For each activated carbon type, phenol was desorbed more readily in the bi-solute case, but desorption of 2-CP was less compared with single-solute. This was attributed to higher energies of 2-CP adsorption.  相似文献   
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In this study, the solid-state reaction mechanism and kinetics were investigated for production of anhydrous sodium metaborate (NaBO2), an industrially and technologically important boron compound. To assess the kinetics of solid-state production of NaBO2, the chemical reaction between borax (Na2B4O7) and sodium hydroxide (NaOH) was investigated by use of the thermal analysis techniques thermogravimetry (TG) and differential thermal analysis (DTA). DTA curves obtained under non-isothermal conditions at different heating rates (5, 10 and 20 °C/min), revealed five endothermic peaks corresponding to five solid-state reactions occurring at 70, 130, 295, 463, and 595 °C. The stages of the solid-state reaction used for production NaBO2 were also analyzed by XRD, which showed that at 70 and 130 °C, Na2B4O7 and NaOH particles contacted between the grains, and diffusion was initiated at the interface. However, there was not yet any observable formation of NaBO2. Formation of NaBO2 was initiated and sustained from 295 to 463 °C, and then completed at 595 °C; the product was anhydrous NaBO2. Activation energies (E a) of the solid-state reactions were calculated from the weight loss based on the Arrhenius model; it was found that in the initial stages of the solid-state reaction E a values were lower than in the last three steps.  相似文献   
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Traditional criterions are not sufficient to predict accurately the recurrence of transitional cell carcinoma of the urinary bladder. Therefore, we aimed to evaluate the AgNORs via total AgNOR area/nucleus area (TAA/NA) for each cell as a prognostic parameter, in TCC of urinary bladder. Tumor tissues of 20 consecutive cases of male bladder cancer patients were divided into two groups as middle differentiated (LG) and high grade (HG). The extra-tumoral tissue (ETT) samples of 10 males served as control group. A second control group (HC) consisted of five healthy and normal bladder tissue samples. The 3 microm of sections from each paraffin embedded tumoral, extra-tumoral and normal tissue samples served as patient and control groups. After deparaffinization and rehydratation steps, silver (AgNO(3)) staining of nucleolar organizer regions-associated proteins (AgNORs) was performed. Instead of Giemsa stain, we used Hematoxylin for contra staining. The images of the 100 analyzable nuclei from each tissue sample, transferred by means of a video camera and video capture card from microscope and recorded onto a computer. Software was prepared in Delphi language for analysis. Mean (E+02) TAA/NA values of HC, ETT, LG and HG groups were 6.97+2.80, 5.70+1.82, 7.80+3.22 and 9.24+3.88, respectively. Statistical comparisons have shown significant differences between all groups.In conclusion, mean TAA/NA per cell has a potential to be a prognostic parameter. Therefore, further evaluation of big patient series will be useful.  相似文献   
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In this study, the thermal behavior in terms of glass transition (T g), degradation, and thermal stability of four commercial new-generation posterior bulk fill composites (Surefill SDR, Dentsply; Quixfill, Dentsply; Xtrabase, Voco; and Xtrafill, Voco) activated by light-emitting diodes (LEDs) was analyzed by thermogravimetric analysis (TG), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). The activation energies (E a) for the decomposition of the dental resins were calculated based on the Kissinger and Doyle kinetic models from the peaks of the endothermic curves obtained when the specimens were heated at four different temperatures (5, 10, 15, and 20 °C min?1) during DSC. The results show that the Xtrabase composite displayed the highest T g (120 °C at a 5 °C min?1 heating rate) and E a (157.64 kJ mol?1) values associated with thermal degradation from the main chain of the polymer.  相似文献   
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In this study, the synthesis of barium metaborate powder (BaB2O4) was carried out by ultrasound-assisted precipitation using different borate solutions. Different solutions such as borax (Na2B4O7, BD), boric acid (H3BO3, BA), and sodium metaborate (NaBO2, SMB) were used in the synthesis and an ultrasonic immersion horn probe was used as the major source of ultrasound. The effect of reaction temperature and time, pH, and crystallization time on the BaB2O4 yield (%) was investigated. The ultrasound-assisted synthesis up to 90 % yield could be achieved using a 0.2 M BD solution at 80 °C, reacting for 5 min at pH 13 followed by 2 h of crystallization. Following crystallization, the obtained powder was heated up to 140, 250, 650, and 750 °C for 2.5 h, and it was shown that β-BaB2O4 nanometric powders were obtained after the 750 °C heat treatment.  相似文献   
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This paper proposes the use of multiagent cooperation for solving global optimization problems through the introduction of a new multiagent environment, MANGO. The strength of the environment lays in its flexible structure based on communicating software agents that attempt to solve a problem cooperatively. This structure allows the execution of a wide range of global optimization algorithms described as a set of interacting operations. At one extreme, MANGO welcomes an individual non-cooperating agent, which is basically the traditional way of solving a global optimization problem. At the other extreme, autonomous agents existing in the environment cooperate as they see fit during run time. We explain the development and communication tools provided in the environment as well as examples of agent realizations and cooperation scenarios. We also show how the multiagent structure is more effective than having a single nonlinear optimization algorithm with randomly selected initial points.  相似文献   
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